Cancer in Pets and People – Can the Similarities Provide a Cure?

When it comes to the dreaded diagnosis of cancer - we all dream of an eventual cure. Believe it or not, thanks to our canine friends, that dream may not be too far away!

By: Dr. Jim Humphries, Veterinary News Network

Finding a cure for cancer is one of science’s most challenging and elusive goals. But beyond defeating this pervasive killer, another important element is to find a way to prevent this disease from ever occurring again! Enter man’s best friend. Thanks to our pets, and the fascinating work of a new breed of scientist, the comparative oncologist, some of the pieces of this complex puzzle are coming together.

The statistics about cancer in our pets are surprising. Estimates from the Morris Animal Foundation state that fifty percent of dogs will develop a cancer at some point in their lifetimes and half of those will die from the disease. For some breeds, the odds are much worse! Sixty percent of Golden Retrievers are said to die from cancer.

As you can imagine, these alarming statistics have gained the attention of many scientists because our dogs and cats often make good models for cancer research and can often improve the advances being made in human medicine. In fact, the field of comparative oncology got its start in the 1970s when researchers were able to perfect bone marrow transplants for people by studying pet dogs with lymphoma. Comparative oncology brings together veterinary oncologists, human medical oncologists, academic cancer research centers and the pharmaceutical industry.

At the National Cancer Institute’s Center for Cancer Research, scientists say that because our pets share our environment and suffer from many naturally occurring cancers, they are probably good indicators of potential causes. In addition, there are many pet cancers that have similar or even identical biological characteristics as human cancers.

But beyond all of the objective data, the strong desire of pet owners to see their beloved dogs and cats live longer means that many new therapeutic options can be tried in order to save the pet. And, since more than 6 million dogs develop cancer each year, veterinarians and cancer researchers can evaluate these new therapies, refine them and potentially provide hope to both pet owners and to the families devastated by a cancer diagnosis.

For example, equipment used for human bone marrow transplants is now available in clinical settings for our pets! In addition the use of a radioactive isotope placed directly into bone tumors by a tiny drill and even the evaluation of specific drugs used to fight certain types of cancer can be used in veterinary medicine. Both research and techniques helping both pets and people is an exciting frontier in medicine.

Perhaps one of the most impressive advancements in comparative oncology is the development of a “canine cancer vaccine”. This novel treatment was recently granted full licensure and is now available for dogs suffering from one of the most common forms of cancer, canine malignant melanoma.

This cancer can be seen in any breed of dog and is highly aggressive. Cancer cells may start in the mouth, footpad or nail bed, but often spread out to infect lymph nodes, liver, lungs or kidneys. For most dogs, a diagnosis of canine malignant melanoma means the pet has just a few months to live, even with surgical treatment. Chemotherapy doesn’t improve survival times either.

But, thanks to research done at Memorial Sloan-Kettering Cancer Center, The Animal Medical Center of New York and Merial, the cancer vaccine (called ONCEPT®) is extending the lives of these dogs and giving hope to humans. In one study with 58 dogs, the researchers were surprisingly unable to determine an exact survival time. Why? Because amazingly more than 50% of the treated dogs were still alive when the study was published! Earlier studies for the vaccine showed that treated pets lived an additional three years after diagnosis.

ONCEPT® uses a human protein to stimulate the dog’s immune system into attacking the cancer cells. Since malignant melanomas have such a tendency to spread throughout the body, this type of treatment helps to find and destroy small cancer clusters even after the main tumor is surgically removed. After the initial set of four vaccines every two weeks, patients receive a “booster” vaccine every 6 months.

The implications of this type of therapy are, of course, amazing for our pets. But further, they could have far reaching positive consequences for human cancer patients as well. Research in comparative oncology is exciting and will no doubt uncover many new potential therapies.

To learn more about the canine cancer vaccine, please visit www.MyVNN.com to see a video. You can also get your pet health questions answered by licensed veterinarians by visiting www.PetDocsOnCall.com.